Psilocybin, or "magic mushrooms," can make people more open in their feelings and aesthetic sensibilities, conferring on them a lasting personality change, according to a study by Johns Hopkins researchers.

People who had mystic experiences while taking the mushrooms were more likely to show increases in a personality trait dubbed "openness," which is related to creativity, artistic appreciation and curiosity, according to the study in the Journal of Psychopharmacology. The change was still in place a year later, suggesting a long-term effect.

"The remarkable piece is that psilocybin can facilitate experiences that change how people perceive themselves and their environment," said Roland Griffiths, a study author and professor of psychiatry and behavioral science at Johns Hopkins University of Medicine in Baltimore. "That's unprecedented."

Magic mushrooms, also known as "shrooms," are hallucinogens native to tropical and subtropical regions of South America, Mexico and the U.S. The fungi were favored by former Harvard psychologist Timothy Leary, who founded the Harvard Psilocybin Project, and explored by ‘60s writer and anthropologist Carlos Castaneda. They are typically eaten but can also be dried and smoked or made into a tea.

Openness is one of five major personality factors known to be constant throughout multiple cultures, heritable in families and largely unvarying throughout a person's lifetime. The other four factors, extroversion, neuroticism, agreeableness and conscientiousness, were unchanged by being dosed with the hallucinogenic mushrooms, the study found. This is the first finding of a short-term intervention providing a long-term personality change, researchers said.

Mystical Experiences

The 51 participants, who had an average age of 46, completed two to five eight-hour drug sessions at least three weeks apart. They were asked to lie down on a couch, use an eye mask and listen to music on headphones while focusing on an inner experience. Their personalities were screened initially, one to two months after each drug session and about a year after the last trip.

In the test, 30 people had a mystical experience, as established by a set of psychological scales. On tests of major personality traits, their openness scores rose, suggesting a greater interest in imagination, aesthetics, feelings, ideas and values. The 22 patients who didn't have a mystical experience showed no change.

Psilocybin mushrooms are a schedule I substance in the U.S., which means the government considers them to have a high potential for abuse and no legitimate medical purpose, according to the National Institute on Drug Abuse.

Griffith disagrees. He has started two studies, one in people distressed by recent diagnoses of cancer, and another in cigarette smokers. The changes to patients' personalities may make them more at ease with their cancer diagnosis or make it easier to give up cigarettes, he said.

"There's reason to suggest a treatment program may help patients in opening the mind to other ways of seeing their behavior," Griffith said.